Conspiracy theories

A short piece for the general audience of RTR radio, Perth, Australia.
(listen to the original audio podcast)

Sadly, some conspiracies are real. Tobacco companies conspired to conceal the truth about their deadly product for decades. Less recently, my own ancestors conspired with Guy Fawkes to blow up the English parliament in 1605.

Given conspiracies are real, and often dangerous, it's important to be on the lookout for them. But we must also be careful that we don’t slide into paranoia and see conspiracies everywhere. The trick is to be able to spot the difference between a genuine consensus and a conspiracy.

Distinguishing scientific consensus from conspiracy is especially important. For there is no more reliable guide to truths about the natural world than a genuine, widespread consensus within the relevant scientific community. If you want to know what will happen if you drop a hunk of sodium in water, for example, your best bet is to find out the consensus view amongst chemists. (Here's a hint: it's fun to watch, but you might lose an arm.)

Nevertheless, some vocal critics of modern climate science declare that the overwhelming scientific consensus that humans are causing the earth to warm is, in effect, a mere conspiracy.

So how do we know who is right? How do we tell consensus from conspiracy?

The first thing to realize is that the claim that climate scientists are conspiring against us is itself a theory — namely a conspiracy theory. Like any other theory, we should believe a conspiracy theory only when there is strong evidence to support it.

Conspiracy theorists sometimes argue that climate scientists and their co-conspirators have something to gain by convincing us that humans are causing global warming. But that's a gross distortion of the truth. If we reasoned that way consistently, then whenever medical researchers discovered a new health hazard we shouldn’t heed their warning, we should accuse them of conspiring against us.

A conspiracy theory also doesn’t become plausible just because attacks on the consensus are treated with skepticism. Physicists are rightly skeptical of people trying to disprove Einstein’s theory of relativity, since that theory is supported by overwhelming evidence. The same is true of climate science and global warming.

Not only is there no evidence in support of the conspiracy theory about climate science, there are tell-tale signs that this theory is mere paranoia. Plausible theories — including plausible conspiracy theories — explain a wide range of facts, are consistent with other sciences and make novel predictions that turn out to be true. The climate science conspiracy theorists don’t spend their time making careful observations and accurate predictions, but instead must work overtime to protect their theory from refutation by challenging evidence and making more and more bizarre and untested speculations. In typical paranoid style, they are forced to extend the net of their fantasy further and further, so that not just some scientists, but almost all of the world’s climate scientists, scientific organizations and governments are in on the fraud. 

So, while we certainly need to be on the lookout for violent conspirators and ruthless tobacco companies, we also need to protect ourselves against paranoid conspiracy theories. Only then can we learn from others who are experts at things we are not. When it comes to global warming, few things could be more important.

[Many thanks to Professor Steve Lewandowsky for helpful comments on this post.]

NOTE: this post is also being "climatecast" by Dr. Nic Damnjanovic from the University of Western Australia on RTR -FM 92.1 at 11.30 AM WAST today. You can listen to the live broadcast online via or download the podcast here.

Posted by Nic Damnjanovic on Wednesday, 22 December, 2010

Creative Commons License The Skeptical Science website by Skeptical Science is licensed under a Creative Commons Attribution 3.0 Unported License.